Method for determining technological parameters of pole piece baking equipment and related device

Abstract

The invention discloses a method for determining technological parameters of pole piece baking equipment and a related device.According to the method, to-be-determined technological parameters serve as input, a flow field is simulated, on the premise that a flow field simulation result meets a preset flow field requirement, a thermal field and a moisture field are simulated, and the technological parameters of the pole piece baking equipment are determined according to the thermal field simulation result and the moisture field simulation result. Whether the technological parameters are matched with the to-be-baked pole piece or not can be determined in the design stage, the problem that the performance of baking equipment prepared in the later period cannot meet the pole piece baking requirement is effectively solved, and workers can conveniently know the temperature and the moisture content of the pole piece in the baking process through the simulation result; and the temperature rise and moisture evaporation process of the pole piece can be controlled from the technical level, the optimization period and the cost investment are shortened, and cost reduction and efficiency improvement are realized.

Description

Technical Field

[0001] This invention relates to a method and related apparatus for determining process parameters of electrode baking equipment, belonging to the field of baking and drying simulation design. Background Technology

[0002] Moisture in the electrode is one of the key factors to be controlled in the lithium battery manufacturing process. Moisture will react with the electrolyte, consume the lithium ions in the electrolyte, reduce the battery capacity, and produce gas during the reaction, which can lead to dangers such as battery swelling and leakage. Therefore, baking equipment is needed to remove moisture from both sides of the electrode.

[0003] Currently, the formulation of process parameters for baking equipment (mainly including the wind speed and temperature of the baking hot air) relies primarily on experience. This often results in the baking equipment being unsuitable for the electrode to be baked, meaning the performance of the baking equipment cannot meet the baking requirements of the electrode. Therefore, there is currently a lack of a method to determine whether the process parameters are suitable for the electrode to be baked during the design phase. Summary of the Invention

[0004] This invention provides a method and related apparatus for determining process parameters of electrode baking equipment, which solves the problems disclosed in the background art.

[0005] According to one aspect of this application, a method for determining process parameters of an electrode baking apparatus is provided, comprising: The process parameters to be determined are input into the flow field as boundary conditions, and a region model is added within the flow field to obtain the flow field model; where the region is the baking area where the electrode to be baked is placed. Based on the flow field model, flow field simulation is performed; If the flow field simulation results meet the preset flow field requirements, the process parameters that meet the preset flow field requirements are used as boundary conditions and input into the thermal field and moisture field respectively. The thermal field and moisture field are added to the flow field model to obtain the coupled model. Among them, the thermal field is the physical field of heat transfer in humid air, and the moisture field is the physical field of moisture transport in the air. The flow field is coupled with the thermal field, the flow field with the moisture field, and the thermal field and the moisture field in the coupled model. Based on the coupling model, thermal field and moisture field simulations are performed; If the thermal field simulation results meet the preset thermal field requirements and the moisture field simulation results meet the preset moisture field requirements, then the process parameters to be determined are the process parameters that are compatible with the electrode to be baked.

[0006] The above method takes the process parameters to be determined as input and simulates the flow field. Under the premise that the flow field simulation results meet the preset flow field requirements, the thermal field and moisture field are simulated. Through the simulation results of the thermal field and moisture field, it is possible to determine whether the process parameters are compatible with the electrode to be baked during the design stage. This effectively avoids the problem that the performance of the baking equipment in the later preparation cannot meet the baking requirements of the electrode. Furthermore, the simulation results make it easier for staff to understand the temperature and moisture content of the electrode during the baking process, which facilitates the technical control of the temperature rise and moisture evaporation process of the electrode, shortens the optimization cycle and reduces the cost investment, thereby achieving cost reduction and efficiency improvement.

[0007] Furthermore, the method also includes: if the flow field simulation results do not meet the preset flow field requirements, adjusting the baking hot air velocity in the process parameters to be determined to obtain new process parameters to be determined, and inputting the new process parameters to be determined as boundary conditions into the flow field to obtain a new flow field model; if the thermal field simulation results do not meet the preset thermal field requirements or the moisture field simulation results do not meet the preset moisture field requirements, adjusting the baking hot air velocity and / or baking hot air temperature in the process parameters to be determined to obtain new process parameters to be determined, and inputting the new process parameters to be determined as boundary conditions into the flow field to obtain a new flow field model.

[0008] If the simulation results do not meet the preset requirements, the above method adjusts the process parameters. Through multiple simulations and adjustments, the corresponding process parameters can be adjusted for different electrodes.

[0009] Furthermore, the region model defines the material and material properties of the electrode to be baked, as well as the material and material properties of the baking region; among them, the material of the electrode material region to be baked is defined as a porous material; if the material properties are changing material properties, a function that can characterize the changing process is used.

[0010] The above method defines the material in the electrode material area to be baked as a porous material and uses functions to represent the changing material properties, making the region model more realistic and thus improving the accuracy of the simulation.

[0011] Furthermore, before performing flow field simulation, the process includes meshing the regions within the flow field model and then performing the flow field simulation based on the meshing results. The region containing the electrode material to be baked has the highest mesh density. Increasing the mesh density in important regions improves simulation accuracy while maintaining simulation efficiency.

[0012] Furthermore, before performing thermal and moisture field simulations, the model also includes meshing the region model in the coupled model. If the meshing results before the thermal and moisture field simulations are inconsistent with the meshing results before the flow field simulations, the meshing and flow field simulations are redone. By redefining the meshing and performing the flow field simulations, the problem of incorrectly extracting subsequent single-coupling flow field data within the mesh can be avoided.

[0013] Furthermore, the region model is a unit region model, and the unit region includes the electrode unit to be baked and the fluid domain above the electrode unit to be baked; wherein, the electrode unit to be baked includes the electrode material area unit and the foil unit; using the unit model instead of the complete model can shorten the simulation time and improve the simulation efficiency.

[0014] Furthermore, when determining whether the flow field simulation results meet the preset flow field requirements, a wind speed streamline diagram is constructed based on the simulation results, and the accuracy of the flow field simulation results is determined based on the wind speed streamline diagram. Similarly, when determining whether the thermal field simulation results meet the preset thermal field requirements, a temperature distribution diagram is constructed based on the thermal field simulation results, and the accuracy of the thermal field simulation results is determined based on the temperature distribution diagram. The graphical display of wind speed streamlines, temperature distribution, and moisture distribution facilitates a quick assessment of whether the simulation results meet the preset requirements.

[0015] According to another aspect of this application, a device for determining process parameters of an electrode baking equipment is provided, comprising: The flow field model module takes the process parameters to be determined as boundary conditions and inputs them into the flow field. It then adds a region model within the flow field to obtain the flow field model. The region is the baking area where the electrode to be baked is placed. The flow field simulation module performs flow field simulation based on the flow field model. The coupled model module, if the flow field simulation results meet the preset flow field requirements, inputs the process parameters that meet the preset flow field requirements as boundary conditions into the thermal field and the moisture field respectively, adds the thermal field and the moisture field to the flow field model to obtain the coupled model; where the thermal field is the physical field of heat transfer in moist air, and the moisture field is the physical field of moisture transport in the air; the flow field is coupled with the thermal field, the flow field with the moisture field, and the thermal field and the moisture field in the coupled model; The thermal and moisture field simulation module performs thermal and moisture field simulations based on the coupled model. If the thermal field simulation results and the moisture field simulation results meet the preset thermal field requirements, then the process parameters to be determined are the process parameters that are compatible with the electrode to be baked.

[0016] The aforementioned device takes the process parameters to be determined as input and simulates the flow field. Under the premise that the flow field simulation results meet the preset flow field requirements, it simulates the thermal field and moisture field. Through the simulation results of the thermal field and moisture field, it can be determined whether the process parameters are compatible with the electrode to be baked during the design stage. This effectively avoids the problem that the performance of the baking equipment in the later preparation cannot meet the baking requirements of the electrode. Furthermore, the simulation results make it easier for staff to understand the temperature and moisture content of the electrode during the baking process, which facilitates the technical control of the temperature rise and moisture evaporation process of the electrode, shortens the optimization cycle and reduces the cost investment, thereby achieving cost reduction and efficiency improvement.

[0017] According to one aspect of this application, a computer-readable storage medium is provided that stores one or more programs, the one or more programs including instructions that, when executed by a computing device, cause the computing device to perform a method for determining process parameters of an electrode baking apparatus.

[0018] The aforementioned storage medium stores the program corresponding to the method for determining the process parameters of the electrode baking equipment. This method can effectively avoid the problem that the performance of the baking equipment prepared later cannot meet the requirements of electrode baking. It also facilitates the technical control of the electrode temperature rise and moisture evaporation process, shortens the optimization cycle and cost investment, and achieves cost reduction and efficiency improvement.

[0019] According to one aspect of this application, a computer device is provided, including one or more processors and one or more memories, wherein one or more programs are stored in the one or more memories and configured to be executed by the one or more processors, and the one or more programs include instructions for performing a method for determining process parameters of an electrode baking apparatus.

[0020] The processor of the above-mentioned device executes the above-mentioned method for determining the process parameters of the electrode baking equipment. This method can effectively avoid the problem that the performance of the baking equipment prepared later cannot meet the requirements of electrode baking. It also facilitates the technical control of the electrode temperature rise and moisture evaporation process, shortens the optimization cycle and cost investment, and achieves cost reduction and efficiency improvement.

[0021] The beneficial effects achieved by this invention are as follows: This invention uses the process parameters to be determined as input to simulate the flow field. Under the premise that the flow field simulation results meet the preset flow field requirements, the thermal field and moisture field are simulated. Through the simulation results of the thermal field and moisture field, it is possible to determine whether the process parameters are compatible with the electrode to be baked during the design stage. This effectively avoids the problem that the performance of the baking equipment in the later preparation cannot meet the baking requirements of the electrode. Furthermore, the simulation results make it easier for staff to understand the temperature and moisture content of the electrode during the baking process, which facilitates the technical control of the temperature rise and moisture evaporation process of the electrode, shortens the optimization cycle and reduces the cost investment, thereby achieving cost reduction and efficiency improvement. Attached Figure Description

[0022] Figure 1 A flowchart illustrating the method for determining process parameters of electrode baking equipment; Figure 2 A schematic diagram of the area; Figure 3 A schematic diagram of grid division; Figure 4 This is a streamline diagram of wind speed. Figure 5 Temperature distribution diagram; Figure 6 A moisture distribution map; Figure 7 A block diagram of the device for determining the process parameters of the electrode baking equipment. Detailed Implementation

[0023] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this application or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0024] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this application.

[0025] At the same time, it should be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn according to actual scale.

[0026] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0027] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0028] It should be noted that similar symbols and letters in the following figures represent similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0029] See figure. Figure 1This is a flowchart illustrating a method for determining process parameters of an electrode baking equipment according to an embodiment of this application. This parameter determination method can be executed by a parameter determining device, which can be a terminal device or a server. The parameter determination method may include at least the following steps: Step 1: Input the process parameters to be determined as boundary conditions into the flow field, add a region model within the flow field, and obtain the flow field model; where the region is the baking area where the electrode to be baked is placed.

[0030] It should be noted that the structure of the region mainly includes the material area, the foil, and the fluid domain around the electrode to be baked; among them, the material area and the foil constitute the electrode to be baked.

[0031] In some embodiments, the region model defines the material and material properties of the electrode to be baked (i.e., the material zone and foil) and the material and material properties of the baking zone (i.e., the fluid domain).

[0032] For example, air can be used as the material in the fluid domain, and density and dynamic viscosity can be used as properties of air. Copper / aluminum can be used as the materials for the negative / positive electrode foils, and density, dynamic viscosity, porosity, and permeability can be used as properties of copper / aluminum. Since the material zone consists of a solid-liquid mixture composed of solid active materials (graphite, lithium iron phosphate, etc.) and liquid binders and conductive agents, the liquid part will evaporate during baking, thus forming pores between the solids. Therefore, the material of the electrode material zone to be baked can be defined as a porous material, and porosity, absolute permeability, relative permeability, relative humidity, thermal conductivity, specific heat capacity, and density can be used as properties of porous materials.

[0033] It should be noted that the above properties can be obtained through experimental measurement or theoretical calculation based on actual conditions. However, if the material properties are variable, such as the relative permeability of air, the relative permeability of the material zone, or the adsorption isotherm, they can be represented by a function that can characterize the change process.

[0034] Here, the material in the electrode material area to be baked is defined as a porous material, and the changing material properties are represented by functions, making the region model more realistic and thus improving the accuracy of the simulation.

[0035] In some embodiments, the region model adopts a unit region model, see [link / reference]. Figure 2 The unit region includes the electrode unit to be baked and the fluid domain above the electrode unit to be baked; the electrode unit to be baked includes the electrode material area unit and the foil unit; using the unit model instead of the complete model can shorten the simulation time and improve the simulation efficiency.

[0036] It should be noted that the process parameters mainly include the wind speed and temperature of the baking hot air. Since the electrode is in motion inside the baking equipment (usually an oven) and the baking temperature is different in different baking stages, the parameters of the hot air received by the electrode will change over time. Therefore, it is necessary to convert the changing wind speed and temperature into functions for expression. The wind speed and temperature will be expressed as functions as inputs.

[0037] Step 2: Perform flow field simulation based on the flow field model; the flow field simulation can obtain data such as wind speed and partial pressure.

[0038] In some embodiments, before performing flow field simulation, the process further includes mesh generation of the region model in the flow field model, and flow field simulation is performed based on the mesh generation results. Higher mesh generation quality results in more accurate simulation results. The region model with the highest mesh generation density is the area containing the electrode material to be baked, as shown in [reference needed]. Figure 3 The finer the mesh in the material area, the better. After the mesh is generated and checked for any problems, the subsequent steps can be carried out.

[0039] In the entire regional model, the material zone is an important region, and the requirements for mesh quality are higher when calculating mass and heat transfer in porous media. Therefore, the mesh density of this region will be increased. This method of increasing the mesh density of important regions (the higher the mesh density, the longer the simulation calculation time and the higher the accuracy) and the smaller the mesh density of other secondary regions can improve the simulation calculation accuracy while ensuring simulation efficiency.

[0040] Step 3: If the flow field simulation results do not meet the preset flow field requirements, adjust the baking hot air velocity in the process parameters to be determined to obtain new process parameters to be determined, and proceed to Step 1; If the flow field simulation results meet the preset flow field requirements, input the process parameters that meet the preset flow field requirements (i.e., the process parameters corresponding to the flow field simulation) as boundary conditions into the thermal field and moisture field respectively, add the thermal field and moisture field to the flow field model to obtain the coupled model; where the thermal field is the physical field of heat transfer in humid air, and the moisture field is the physical field of moisture transport in the air; in the coupled model, the flow field is coupled with the thermal field, the flow field is coupled with the moisture field, and the thermal field and moisture field are coupled.

[0041] It should be noted that the coupling here is bidirectional coupling, that is, the two lengths influence each other. Therefore, in the coupling model, the three fields influence each other in pairs.

[0042] The preset flow field requirements can be set as follows: the wind direction within the material area is reasonable with no eddies, and the wind speed is uniform and stable.

[0043] To facilitate the interpretation of flow field simulation results, in some embodiments, a wind speed streamline diagram is first constructed based on the flow field simulation results. (See [link to relevant documentation]). Figure 4The simulation results are used to determine whether they meet the preset flow field requirements based on the wind speed streamline diagram. The graphical display of the wind speed streamline facilitates a quick assessment of whether the simulation results meet the preset requirements.

[0044] It should be noted that before performing thermal and moisture field simulations, the region model in the coupled model is also meshed. If the meshing results before the thermal and moisture field simulations are inconsistent with the meshing results before the flow field simulations, the meshing and flow field simulations are redone. By redefining the meshing and performing the flow field simulations, the problem of incorrectly extracting subsequent single-coupling flow field data within the mesh can be avoided.

[0045] Step 4: Based on the coupled model, perform thermal and moisture field simulations; the simulation results are the temperature and moisture distribution of the region model.

[0046] Step 5: If the thermal field simulation result does not meet the preset thermal field requirements or the moisture field simulation result does not meet the preset moisture field requirements, adjust the baking hot air velocity and / or baking hot air temperature in the process parameters to be determined (the specifics need to be determined according to the actual situation) to obtain new process parameters to be determined, and go to step 1; if the thermal field simulation result meets the preset thermal field requirements and the moisture field simulation result meets the preset moisture field requirements, then the process parameters to be determined are the process parameters that are compatible with the electrode to be baked.

[0047] It should be noted that the preset thermal field requirement can be set to uniform temperature and temperature value that meets the corresponding process requirements of the electrode, such as the heating curve of the electrode meeting the process requirements; the preset moisture field requirement can be set to the moisture content after baking that meets the corresponding process requirements of the electrode.

[0048] Similarly, to facilitate the evaluation of simulation results, in some embodiments, a temperature distribution map will be constructed based on the thermal field simulation results, see [link to relevant documentation]. Figure 5 Based on the temperature distribution map, determine whether the thermal field simulation results meet the preset thermal field requirements; construct a moisture distribution map based on the moisture field simulation results (see [link]). Figure 6 The simulation results of the moisture field are used to determine whether they meet the preset moisture field requirements based on the moisture distribution map. Graphical display of temperature and moisture distribution facilitates quick assessment of whether the simulation results meet the preset requirements.

[0049] The above method takes the process parameters to be determined as input and simulates the flow field. Under the premise that the flow field simulation results meet the preset flow field requirements, the thermal field and moisture field are simulated. Through the simulation results of the thermal field and moisture field, it can be determined whether the process parameters are suitable for the electrode to be baked during the design stage. This effectively avoids the problem that the performance of the baking equipment in the later preparation cannot meet the baking requirements of the electrode. If the simulation results do not meet the preset requirements, the process parameters are adjusted. Through multiple simulations and adjustments, the corresponding process parameters can be adjusted for different electrodes. Furthermore, the simulation results make it easier for staff to understand the temperature and moisture content of the electrode during the baking process, which facilitates the technical control of the temperature rise and moisture evaporation process of the electrode, shortens the optimization cycle and reduces the cost investment, thereby achieving cost reduction and efficiency improvement.

[0050] It should be noted that the above method can be implemented based on existing multiphysics simulation software. The following description uses COMSOL, which is commonly used in this field, as an example. The implementation process of the above method can be as follows: 1) In any 3D modeling software, establish a region model (i.e., a 3D region model). To shorten computation time and improve computational efficiency, a small portion of the electrode to be baked is taken as a micro-element electrode (i.e., the electrode unit to be baked) for simulation. The air domain at a certain height above the micro-element electrode is taken as the fluid domain. (See [link to relevant documentation]). Figure 2 This converts the region model into a common format for 3D software, such as Parasolid.

[0051] 2) Open the COMSOL software, create a new 3D simulation model, select "Heat Transfer > Heat and Moisture Transfer > Heat and Moisture Flow > Turbulence > k-epsilon" for the physics field, and select "Transient" for the study. This will generate three coupled physics field models: "Turbulence (i.e., flow field)," "Moisture Transport in Air (i.e., moisture field)," and "Moisture Transfer in Moist Air (i.e., heat field)." Import the general format region 3D model into the 3D simulation model.

[0052] It should be noted that since COMSOL software can automatically generate and couple these three physical fields, to simplify the operation, you can initially generate these three physical fields directly. The simulation should initially focus on the flow field without setting up the thermal and moisture fields. Once the flow field and wind speed are satisfactory, then add the thermal and moisture fields for further simulation. Alternatively, you can follow the steps described above: first create the flow field, then perform the flow field simulation, then create the other two fields, set up coupling, and then perform the thermal and moisture field simulations.

[0053] It should be noted that since the 3D model has already been established in step 1), there is no need to process the model further. Simply select "Form Union" in the geometry menu to ensure that the mesh intersections of the subsequent solid domain and fluid domain are consistent.

[0054] 3) Select common materials and material properties, and create specific materials and material properties.

[0055] Air can be used as a material in the fluid domain, with density and dynamic viscosity as properties of air.

[0056] Copper and aluminum are used as the negative and positive electrode foil materials, respectively, and their properties are density, dynamic viscosity, porosity, and permeability.

[0057] Since the electrode material region is composed of a solid-liquid mixture of solid active materials (graphite, lithium iron phosphate, etc.) and liquid binders and conductive agents, the liquid portion evaporates during baking, creating pores between the solids. Therefore, the electrode material region can be treated as a porous medium. The material properties of the electrode material region can be obtained through experimental measurement or theoretical parameters, depending on the actual situation. The parameters involved may include: porosity, absolute permeability, relative permeability, relative humidity, thermal conductivity, specific heat capacity, and density of the electrode material region.

[0058] The relative permeability of air, the relative permeability of the electrode material zone, and the adsorption isotherm, among other changing input parameters, can be expressed using functions. Specifically, these can be set using "Component > Definition > Function". The material properties of the porous medium need to be created manually. The specific steps are: Right-click the material under the Material node, select "More Materials > Porous Materials", select the electrode material zone within the Porous Material node, right-click the porous material, select "Solid", navigate to the Solids property bar, and enter the solid volume fraction, which is one minus the porosity of the material zone. Within the Solids node, navigate to the Material Properties Details bar and enter the "thermal conductivity, specific heat capacity, and density of the electrode material zone". Return to the Porous Materials node, navigate to the Homogeneity property bar, and enter the "diffusion coefficient, water content, permeability, and porosity of the porous medium"; where the diffusion coefficient... , For the humidity of porous media, Porosity This represents the solid density. The water content depends on the adsorption isotherm, which is a function of relative humidity. Therefore, relative humidity needs to be added as a variable: Select "Basic" in the Porous Material node, locate the model input bar, and select "General > Relative Humidity" in Add Physical Quantities.

[0059] 4) Obtain process parameters. The process parameters mainly include the wind speed and temperature of the baking hot air, as well as the initial temperature and humidity inside the baking equipment and the initial temperature and humidity of the electrode sheet.

[0060] The designed wind speed and temperature can be obtained through simulation of the thermal flow field during baking. When determining whether existing baking equipment is compatible with the electrode, actual process parameters can be obtained through monitoring. For example, the actual monitored temperature is usually obtained by online temperature measuring devices such as thermocouples or by handheld detection devices such as thermal imagers. The actual monitored wind speed is usually the stable average value of flow rate, velocity, or pressure measuring instruments. Humidity values ​​can be obtained by sampling and detecting with a Karl Fischer moisture meter. This application uses wind speed and temperature as input conditions for the velocity inlet, an open boundary as input conditions for the pressure outlet, and humidity as the initial condition for the baking area and the electrode moisture value.

[0061] Since the electrode is in motion within the baking equipment and the baking temperature varies at different stages, the parameters of the hot air received by the electrode will change over time. Therefore, it is necessary to convert the changing wind speed and temperature into a function and then use the function as an input parameter. This can be set in "Components > Definitions > Functions".

[0062] 5) Input the process parameters (mainly the wind speed and temperature of the baking hot air) as boundary conditions into the turbulent physical field (i.e., the flow field), and select the region model in the flow field; locate the physical model bar under the "Turbulence, k-epsilon" node, select fluid compressibility, and calculate the compressibility of the actual fluid according to the formula, which is that the Mach number Ma is equal to the flow velocity divided by the speed of sound. This application uses compressible flow (Ma < 0.3); since the electrode material area is regarded as a porous medium domain, this feature needs to be enabled. Select "Enable Porous Medium Domain" under compressibility, and adjust according to the electrode size. Considering whether to add gravity, since this application uses micro-element electrodes, the effect of gravity on fluid transport can be ignored. Add a porous media node by right-clicking the "Turbulence, k-epsilon" node, selecting porous media, and choosing the electrode material area as this domain. Select "Porous Matrix 1," navigate to the basic properties panel, and select "User Defined" in the porosity panel to input the porosity. Since the electrode material area is considered as a porous matrix and fluid, where the fluid is liquid water and humid air, the porosity is the volume occupied by humid air. This porosity will change with the saturation of liquid water. The porosity used in this application... ,in θ f It represents the fluid volume fraction. mt.sl Set the liquid water saturation; locate the permeability attribute bar and select "User Defined". Here, the permeability value is the absolute permeability multiplied by the relative permeability; input the hot air velocity as the velocity inlet; set the area around the electrode as an open boundary with zero normal stress. The inlet with zero normal stress refers to the surface of the micro-element electrode that communicates with the inside of the baking equipment, the cross section of the micro-element electrode that connects with the entire electrode in the thickness direction, and the relative pressure is zero.

[0063] 6) Mesh generation: After the mesh is generated, check for any problems and proceed to the next step. If an error occurs, modify the faulty mesh and proceed to the next step after repairing the mesh. Figure 3 For the meshing of this application, the finer the mesh in the electrode material area, the better. This application selects the "Extremely Fine" predefined mesh size in the "Fluorodynamics" calibration for this area.

[0064] 7) Flow field calculation and analysis: In the new study, select steady state in the solver and perform flow field simulation calculations. Since this application focuses on whether the wind direction within the electrode material area is reasonable and free of eddies, and whether the wind speed is uniform and stable, steady state is used to calculate the flow field results. If the steady-state results do not converge due to flow field instability, the wind speed parameters need to be modified and the calculation recalculated until steady-state results are output.

[0065] When choosing a solver, you can use either a direct solver or an iterative solver. Direct solvers are faster and more accurate, but they have higher space complexity, place higher demands on workstations or servers, and in some cases, the results are not easy to converge. Iterative solvers take longer, but they consume fewer computational resources, and within a certain acceptable error range, the results are more likely to converge.

[0066] 8) Post-process the flow field results, create a 3D plotting group, right-click the 3D plotting group and select "streamline", select the wind speed inlet; right-click the streamline and select "color expression" to draw the wind speed streamline diagram, and judge whether the wind speed on the electrode surface meets the requirements based on the results of the 3D plotting group; Figure 4 This is a wind speed streamline diagram. If the streamline direction or wind speed does not meet expectations, or if eddies exist, the wind speed parameters need to be adjusted and the flow field results recalculated until the expected results are achieved.

[0067] Flow field simulation results are fundamental to ensuring effective baking. If the flow field results are flawed, subsequent adjustments to the baking temperature will be ineffective. However, the flow field results only characterize the speed and direction of the hot air, not the distribution of temperature and moisture. Therefore, two-phase flow heat and moisture transfer calculations are needed to determine the temperature and humidity of the electrode. During baking, moisture inside the electrode evaporates into water vapor, which then escapes from the electrode and mixes with dry air inside the baking equipment before being discharged through the equipment's outlet. Therefore, there is no liquid water inside the baking equipment; all moisture leaves the porous medium as vapor. This process can be calculated in COMSOL using a two-phase flow heat and moisture transfer mechanism that couples the "moisture transport in air" and "heat transfer in humid air" interfaces.

[0068] 9) Begin the simulation setup for the air moisture transport interface. After the flow field calculation is completed and confirmed to be problem-free, input the process parameters as boundary conditions into the air moisture transport interface. Select the region model in the air moisture transport interface; set the initial humidity of the air in the initial value node; add a porous media node, right-click the "Air Moisture Transport" node, select hygroscopic porous media, and select the electrode material area as this region. Select "Hygroscopic Porous Media 1", locate the moisture transport attribute bar, and select "Diffusion" in the capillary model list. In the "Hygroscopic Porous Media 1" node, select "Liquid Water 1", locate the liquid water attribute bar, and input the relative permeability of water. Add the initial humidity of the electrode material area, right-click the "Air Moisture Transport" node, select "Initial Value", and set the humidity of the porous media in the initial value node; input the hot air inlet as the inflow boundary and input the internal temperature and humidity of the baking equipment; set the area around the electrode as an open boundary and input the internal temperature and humidity of the baking equipment. The open boundary refers to the surface of the micro-element electrode that communicates with the interior of the baking equipment.

[0069] 10) Start the simulation settings for the humid air heat transfer interface. Input the process parameters as boundary conditions into the humid air heat transfer interface. Select all domains in the humid air heat transfer interface. The foil material can be set as a solid domain, a thin layer, or simplified to a surface, depending on the actual situation. In this application, the foil material is set as a surface. Select all domains in the humid air heat transfer interface and set the initial temperature in the initial value node. Add a porous medium node. Right-click the "humid air heat transfer" node and select the humid porous medium in the specific medium. Select the electrode material area as the domain. Select "Porous substrate 1", locate the basic attribute bar, and select solid phase attribute in the definition list. Input the hot air inlet as the inflow boundary and input the internal temperature of the baking equipment. Set the area around the electrode as an open boundary and input the internal temperature of the baking equipment. The open boundary refers to the surface of the micro-element electrode that communicates with the inside of the baking equipment and the cross section of the micro-element electrode that connects with the entire electrode in the thickness direction.

[0070] 11) Perform multi-physics coupling simulation calculations of heat and moisture transfer in two-phase flow and moisture transport in porous media. The results of flow field, thermal field and moisture field affect each other, so bidirectional coupling is adopted: When selecting the physical field in the second step, the required multi-physics field should be automatically coupled. Among them, "turbulent flow, k-epsilon" and "moist air heat transfer" are coupled in the "non-isothermal flow" node, "turbulent flow, k-epsilon" and "moisture transport in air" are coupled in the "moisture flow" node, and "moisture transport in air" and "moist air heat transfer" are coupled in the "heat and moisture" node.

[0071] 12) Create a new study to calculate the transient results of fluid flow and evaporation in porous media. First, use the steady-state results of the flow field as the initial values ​​for calculating the transient results. In the solver, select steady state and drag it above the transient step established in the second step. In the steady-state multiphysics coupling interface, uncheck "Moisture transport in air" and "Heat transfer in humid air". In the transient multiphysics coupling interface, locate the study settings and input / output time steps and tolerances. Click "Calculate" to start the two-way coupled simulation calculation of the flow field, thermal field, and moisture field.

[0072] 13) After the bidirectional coupled simulation calculations of the flow field, thermal field, and moisture field are completed, post-processing is performed. A 3D plotting group for temperature and moisture content is created. Right-click on "3D Plotting Group," select "Rename," and name the plotting group "Temperature Section." In the Dataset section of the Data pane, select the study established in step thirteen. The time list below allows you to select the desired time step. Insert a temperature section: Right-click on "Temperature Section," select "Section," enter "T" in the Expression bar, select "degC" as the unit, enter the section position data in the Planar Data bar, adjust the color table in the Shading and Style bar, and draw a temperature distribution map. Use the results of the 3D plotting group to determine if the temperature uniformity meets the requirements and if the temperature value meets the process requirements. The 3D plotting group for moisture content is set up in the same way as the temperature 3D plotting group, except that the Expression bar is changed to "mt.phi." Use the results of the 3D plotting group to determine if the moisture content after electrode baking meets the process requirements. See [link to relevant documentation] Figure 5 and 6 If the temperature uniformity or moisture content does not meet the requirements, the wind speed or temperature parameters need to be adjusted, and the two-way coupled simulation of the flow field, thermal field and moisture field needs to be recalculated until the temperature uniformity and moisture content meet the requirements.

[0073] 14) Generate a simulation report.

[0074] See Figure 7 , Figure 7 This is a block diagram of a process parameter determination device for electrode baking equipment provided in an embodiment of this application. Figure 7 An embodiment is a virtual device that can be loaded and executed by a computer device, which may include the aforementioned parameter determining device. Figure 7 The device may include at least a flow field model module, a flow field simulation module, a coupling model module, a thermal field and moisture field simulation module, and a determination module.

[0075] The flow field model module takes the process parameters to be determined as boundary conditions and inputs them into the flow field. It adds a region model within the flow field to obtain the flow field model; where the region is the baking area where the electrode to be baked is placed.

[0076] The flow field simulation module performs flow field simulation based on the flow field model.

[0077] In the coupled model module, if the flow field simulation results meet the preset flow field requirements, the process parameters that meet the preset flow field requirements are used as boundary conditions and input into the thermal field and moisture field respectively. The thermal field and moisture field are added to the flow field model to obtain the coupled model. Among them, the thermal field is the physical field of heat transfer in humid air, and the moisture field is the physical field of moisture transport in the air. The flow field and the thermal field, the flow field and the moisture field, and the thermal field and the moisture field are all coupled in the coupled model.

[0078] The thermal and moisture field simulation module performs thermal and moisture field simulations based on the coupled model.

[0079] If the thermal field simulation results and the moisture field simulation results meet the preset thermal field requirements, then the process parameters to be determined are the process parameters that are compatible with the electrode to be baked.

[0080] The aforementioned device takes the process parameters to be determined as input and simulates the flow field. Under the premise that the flow field simulation results meet the preset flow field requirements, it simulates the thermal field and moisture field. Through the simulation results of the thermal field and moisture field, it can be determined whether the process parameters are compatible with the electrode to be baked during the design stage. This effectively avoids the problem that the performance of the baking equipment in the later preparation cannot meet the baking requirements of the electrode. Furthermore, the simulation results make it easier for staff to understand the temperature and moisture content of the electrode during the baking process, which facilitates the technical control of the temperature rise and moisture evaporation process of the electrode, shortens the optimization cycle and reduces the cost investment, thereby achieving cost reduction and efficiency improvement.

[0081] This application also relates to a computer-readable storage medium that stores one or more programs, the one or more programs including instructions that, when executed by a computing device, cause the computing device to perform a method for determining process parameters of an electrode baking apparatus.

[0082] The aforementioned storage medium stores the program corresponding to the method for determining the process parameters of the electrode baking equipment. This method can effectively avoid the problem that the performance of the baking equipment prepared later cannot meet the requirements of electrode baking. It also facilitates the technical control of the electrode temperature rise and moisture evaporation process, shortens the optimization cycle and cost investment, and achieves cost reduction and efficiency improvement.

[0083] This application also relates to a computer device including one or more processors and one or more memories, wherein one or more programs are stored in the one or more memories and configured to be executed by the one or more processors, and the one or more programs include instructions for performing a method for determining process parameters of an electrode baking apparatus.

[0084] The processor of the above-mentioned device executes the above-mentioned method for determining the process parameters of the electrode baking equipment. This method can effectively avoid the problem that the performance of the baking equipment prepared later cannot meet the requirements of electrode baking. It also facilitates the technical control of the electrode temperature rise and moisture evaporation process, shortens the optimization cycle and cost investment, and achieves cost reduction and efficiency improvement.

[0085] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0086] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0087] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0088] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0089] The above are merely embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application shall be included within the scope of the claims of this application pending approval.

Claims

1. A method for determining process parameters of electrode baking equipment, characterized in that, The method comprises the following steps: inputting the to-be-determined process parameter as a boundary condition into a flow field, adding a region model in the flow field, and obtaining a flow field model; wherein the region is a baking region in which an electrode piece to be baked is placed; performing flow field simulation according to the flow field model; if the flow field simulation result meets preset flow field requirements, inputting the process parameter meeting the preset flow field requirements as a boundary condition into a thermal field and a moisture field, adding the thermal field and the moisture field in the flow field model, and obtaining a coupling model; wherein the thermal field is a wet air heat transfer physical field, and the moisture field is a water transport physical field in air; the flow field, the thermal field, the moisture field, and the thermal field and the moisture field are coupled in the coupling model; performing thermal field and moisture field simulation according to the coupling model; if the thermal field simulation result meets preset thermal field requirements and the moisture field simulation result meets preset moisture field requirements, the to-be-determined process parameter is a process parameter adapted to the electrode piece to be baked.

2. The method of claim 1, wherein, The method further comprises the following steps: if the flow field simulation result does not meet the preset flow field requirements, adjusting a baking hot air speed in the to-be-determined process parameter to obtain a new to-be-determined process parameter, inputting the new to-be-determined process parameter as a boundary condition into the flow field, and reobtaining the flow field model; if the thermal field simulation result does not meet the preset thermal field requirements or the moisture field simulation result does not meet the preset moisture field requirements, adjusting the baking hot air speed and / or a baking hot air temperature in the to-be-determined process parameter to obtain a new to-be-determined process parameter, inputting the new to-be-determined process parameter as a boundary condition into the flow field, and reobtaining the flow field model.

3. The method of claim 1, wherein, In the region model, the material and material properties of the electrode piece to be baked and the material and material properties of the baking region are defined; wherein the material of the electrode piece to be baked is defined as a porous material; if the material properties are variable material properties, a function capable of representing a change process is used.

4. The method of claim 1, wherein, Before the flow field simulation is performed, the region model in the flow field model is further meshed, and the flow field simulation is performed according to the meshing result; wherein the meshing density of the electrode piece to be baked in the region model is the largest.

5. The method of claim 4, wherein, Before the thermal field and moisture field simulation are performed, the region model in the coupling model is further meshed, and if the meshing result before the thermal field and moisture field simulation is inconsistent with the meshing result before the flow field simulation, the meshing and the flow field simulation are performed again.

6. The method of claim 1, 3, 4, or 5, wherein, The region model is a unit region model, and the unit region comprises an electrode piece unit to be baked and a fluid domain above the electrode piece unit to be baked; wherein the electrode piece unit to be baked comprises an electrode piece material unit and a foil unit.

7. The method of claim 1, wherein, When it is judged whether the flow field simulation result meets the preset flow field requirements, a wind speed streamline diagram is constructed according to the flow field simulation result, and whether the flow field simulation result meets the preset flow field requirements is judged according to the wind speed streamline diagram; When it is judged whether the thermal field simulation result meets the preset thermal field requirements, a temperature distribution diagram is constructed according to the thermal field simulation result, and whether the thermal field simulation result meets the preset thermal field requirements is judged according to the temperature distribution diagram; When it is judged whether the moisture field simulation result meets the preset moisture field requirements, a moisture distribution diagram is constructed according to the moisture field simulation result, and whether the moisture field simulation result meets the preset moisture field requirements is judged according to the moisture distribution diagram.

8. An electrode baking apparatus process parameter determination device, characterized by, The method comprises the following steps: The flow field model module inputs the to-be-determined process parameter as a boundary condition into the flow field, adds a region model in the flow field, and obtains a flow field model; the region is a baking region in which the pole piece to be baked is placed; The flow field simulation module simulates the flow field according to the flow field model; The coupling model module inputs the process parameter meeting the preset flow field requirement as a boundary condition into the thermal field and the moisture field, adds the thermal field and the moisture field in the flow field model, and obtains a coupling model, if the flow field simulation result meets the preset flow field requirement; the thermal field is a wet air heat transfer physical field, and the moisture field is an air moisture transport physical field; the flow field, the thermal field, the moisture field, and the thermal field and the moisture field are coupled in the coupling model; The thermal field and moisture field simulation module simulates the thermal field and the moisture field according to the coupling model; The determination module determines that the to-be-determined process parameter is the process parameter adapted to the pole piece to be baked, if the thermal field simulation result meets the preset thermal field requirement, and the moisture field simulation result meets the preset moisture field requirement.

9. A computer-readable storage medium, characterized in that, The computer readable storage medium stores one or more programs, and the one or more programs include instructions that, when executed by a computing device, cause the computing device to perform the method of any one of claims 1-7.

10. A computer device, comprising: Comprise: One or more processors and one or more memories, one or more programs are stored in the one or more memories and configured to be executed by the one or more processors, and the one or more programs include instructions for executing the method of any one of claims 1-7.

Images